package org.smart4j.charpter2.util;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 属性文件工具类
 * @author 蒋贵强
 *
 */
public final class PropsUtil {

	private static final Logger LOGGER = LoggerFactory.getLogger(PropsUtil.class);
	
	/**
	 * 加载属性文件
	 * @param filename
	 * @return
	 */
	public static Properties loadProps(String filename){
		Properties props = null;
		InputStream is = null;
		try{
//			LOGGER.info(Thread.currentThread().getContextClassLoader().getResource(filename).toString());
			is = Thread.currentThread().getContextClassLoader().getResourceAsStream(filename);
			if(is == null){
				throw new FileNotFoundException(filename+" is not found");
			}
			props = new Properties();
			props.load(is);
		}catch(IOException e){
			LOGGER.error("load properties file failure", e);
		}finally {
			if(is != null){
				try {
					is.close();
				} catch (IOException e) {
					LOGGER.error("close input  Stream failure", e);
				}
			}
		}
		return props;
	}
	
	/**
	 * 获取字符型属性，默认为空串
	 * @param props
	 * @param key
	 * @return
	 */
	public static String getString(Properties props,String key){
		return getString(props,key,"");
	}
	
	/**
	 * 获取字符型属性（制度默认值）
	 * @param props
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static String getString(Properties props,String key,String defaultValue){
		String value = defaultValue;
		if(props.contains(key)){
			value = props.getProperty(key);
		}
		return value;
	}
	
	/**
	 * 获取int型属性，默认为0
	 * @param props
	 * @param key
	 * @return
	 */
	public static int getInt(Properties props,String key){
		return getInt(props, key, 0);
	}
	
	/**
	 * 获取int型属性，指定默认值
	 * @param props
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static int getInt(Properties props,String key,int defaultValue){
		int intValue = defaultValue;
		if(props.containsKey(key)){
			intValue = CastUtil.castInt(props.getProperty(key));
		}
		return intValue;
	}
	
	/**
	 * 获取boolean型属性，默认为false
	 * @param props
	 * @param key
	 * @return
	 */
	public static boolean getBoolean(Properties props,String key){
		return getBoolean(props,key,false);
	}
	
	/**
	 * 获取boolean型属性，指定默认值
	 * @param props
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static boolean getBoolean(Properties props,String key,boolean defaultValue){
		boolean value = defaultValue;
		if(props.containsKey(key)){
			return CastUtil.castBoolean(props.getProperty(key));
		}
		return value;
	}
}
